Articles tagged with Excitons
Researchers have presented an overview of recent progress in moiré photonics and optoelectronics, highlighting the emergence of novel quantum phenomena and their potential applications. Moiré superlattices introduce a new paradigm for engineering band structures and exotic quantum states.
Researchers predict that layered electronic 2D semiconductors can host a quantum phase of matter called the supersolid. A solid becomes 'super' when its quantum properties match those of superconductors, simultaneously having two orders: solid and super. The study reports the complete phase diagram of this system at low temperatures.
Researchers have developed a new type of OLED display that uses strong coupling of light and matter to improve color saturation and brightness. The displays, known as polariton-based OLEDs, achieve this without compromising efficiency or viewing angle dependency.
Scientists have directly observed ultrafast motion of nonequilibrium excitons in monolayers WSe2, MoWSe2, and MoSe2, traveling at least 200 nm within 1 ps. This 'superdiffusion' process could break the traditional limitation of photovoltaic efficiency and be used for ultrafast electronic devices.
Researchers have observed exciton quasiparticles confined in atomically thin materials, opening paths to controlling excitons for quantum and optolectronic applications. Custom-built materials can now be designed to confine and manipulate excitons.
Researchers discuss the construction, properties, and applications of 2D/quasi-2D perovskite-based heterostructures. These heterostructures offer novel functionalities for photovoltaic solar cells, LEDs, and photodetectors.
Researchers at IBS CSLM discovered pair quasiparticles in a classical system of microparticles driven by viscous flow. These long-lived excitations exhibit anti-Newtonian forces that stabilize pairs, similar to the behavior of Dirac quasiparticles in graphene.
KAUST researchers have designed and built novel organic scintillator materials for detecting X-rays at low doses, overcoming stability issues with existing ceramic or perovskite materials. The new approach uses heavy atoms to improve X-ray absorption capability and exciton utilization efficiency.
Researchers from City University of Hong Kong developed a novel device-engineering strategy to suppress energy conversion loss in organic photovoltaics, achieving PCE over 19%. The discovery enables OPVs to maximize photocurrent and overcome the limit of maximum achievable efficiency.
Researchers developed a new fluorescent emitter with a small Stokes shift, achieving high external quantum efficiency over 10% and narrow emission bands. The sensitization strategy using TADF sensitizer is an effective method for obtaining efficient electroluminescent devices.
Scientists developed a novel exciton with intralayer charge-transfer characteristics in a moiré superlattice, exceeding conventional parameterized models. The discovery has potential applications in optical sensors and communication technology.
Researchers from University of Warsaw create spiking neuron using photons to mimic biological brain's behavior. This achievement paves the way for photonic neural networks that process information faster and more efficiently than conventional systems.
Australian researchers have engineered a quantum box for polaritons in a two-dimensional material, achieving large polariton densities and a partially 'coherent' quantum state. The novel technique allows researchers to access striking collective quantum phenomena and enable ultra-energy-efficient technologies.
Scientists at Swinburne University of Technology and FLEET collaborators observe and explain signatures of Fermi polaron interactions in atomically-thin WS2 using ultrafast spectroscopy. Repulsive forces arise from phase-space filling, while attractive forces lead to cooperatively bound exciton-exciton-electron states.
Researchers at Dalian Institute of Chemical Physics controlled the fine structure splitting of lead halide perovskite quantum dots by inducing lattice distortion. This allows for coherent quantum beating, a crucial phenomenon in quantum information science.
Researchers at Columbia University have discovered a way to visualize magnons in a 2D material, CrSBr, by pairing them with excitons that emit light. This breakthrough enables the observation of tiny changes in magnon spins, potentially leading to the development of more efficient quantum information networks.
Researchers have coupled different types of electron-hole pairs in molybdenum disulfide, merging their properties to create novel particles. This breakthrough enables the production of individual photons with adjustable properties, paving the way for quantum communication applications.
A homemade microspectrometer invented by Dr. Jamie Laird enables scientists to image defects in perovskite solar cells, improving stability and efficiency. This innovative technique has the potential to revolutionize next-generation photovoltaics, including space missions.
A research team from the University of Göttingen has observed the build-up of dark Moiré interlayer excitons for the first time using femtosecond photoemission momentum microscopy. This breakthrough allows scientists to study the optoelectronic properties of new materials in unprecedented detail.
Researchers developed a simple and versatile nanoparticle ink made from tin oxide, which can be printed at relatively low temperatures using microwave technology. This ink enables the mass production of high-efficiency perovskite solar cells with power-conversion efficiencies of up to 18%.
A KAUST-led team developed organic semiconductor-based photocatalysts to store solar energy as clean hydrogen fuel. These catalysts can absorb visible light and generate long-lived charges, improving efficiency for hydrogen evolution.
A new method for creating key components of solar cells, X-ray detectors, and LEDs uses water to control the growth of phase-pure perovskite crystals. This approach allows for precise tuning of crystal structures at room temperature.
Researchers have discovered stable and mobile excitons in metal, a breakthrough that could speed up digital communication. Excitons can travel rapidly through metal without electrical charge, making them promising candidates as an alternative to free electrons.
Researchers have imaged and measured the two parts of a unique particle called moiré exciton, extending their lifespan. They found that excitons are localized in tiny pockets of around 1.8 nanometers, forming in places where energy is minimal.
For the first time, researchers have imaged the full structure of trapped excitons, a breakthrough that could lead to new semiconductor technologies. The study reveals detailed insights into the behavior of excitons, including their size, motion, and stability.
Scientists have developed a new spectroscopy technique to directly measure the binding energy of biexcitons in WS2, providing insights into their dynamics and characteristic energy scales. The findings inform the development of novel devices such as compact lasers and chemical sensors.
Researchers from the University of Würzburg have discovered new states in 2D materials by exploring their interactions with phonons. This breakthrough enables the creation of hybridized exciton-photon-phonon states, which could lead to room-temperature Bose-Einstein condensation and polariton lasing.
Researchers discovered a novel type of magnet, the antiferromagnetic excitonic insulator, which involves strong magnetic attraction between electrons in a layered material. The new state emerges when electrons form bound pairs with holes and trigger an antiferromagnetic alignment of adjacent electron spins.
Researchers have created and detected dispersing excitons in a metal using angle-resolved photoemission spectroscopy, a breakthrough that could enable efficient data transmission. The discovery of mobile excitons in TaSe3 reveals their mobility and potential to revolutionize electronics.
Researchers use ARPES to study quasi-one-dimensional metallic TaSe3 and observe multiple mobile excitons manifested as sidebands. The excitons have different internal structures depending on the involvement of holes and electrons from the same chain or neighboring ones.
Researchers at the ARC Centre of Excellence in Exciton Science created the first-ever 2D map of the Overhauser field in organic LEDs, revealing local spin variations that can impact device performance. The study highlights challenges in miniaturizing organic-based sensing technologies for practical applications.
A team of researchers proposed a novel approach to spintronics, demonstrating dissipationless conversion between magnetic spin and electric charge in an emergent superfluid in 2D materials. This breakthrough could lead to the development of more efficient spintronic devices.
The study reveals that manipulating the transition dipole moment of excitons in quantum dots can suppress Auger recombination. By combining with external structures, researchers achieved a new way to control the nonradiative process, potentially leading to improved efficiency of QD-based devices.
Researchers from Münster, Bayreuth, and Berlin have proposed a new way of preparing quantum systems to generate single photon states. The proposed method uses a swing-up process in the quantum system to separate generated photons from exciting laser pulses, which is promising for applications.
Researchers have demonstrated a novel topology arising from losses in hybrid light-matter particles, introducing a new avenue to induce topological effects. The study found that the mere presence of loss in an exciton-polariton system causes it to exhibit nontrivial topology.
Researchers have developed a room-temperature perovskite polariton parametric oscillator, enabling scalable and low-threshold nonlinear devices. This breakthrough offers possibilities for the development of cost-effective and integrated polaritonic devices.
Scientists reveal an ultrafast and high-yield polaronic exciton dissociation mechanism in 2D perovskites, contradicting previous theories. This study confirms that free-carriers dominate charge carriers in 2D perovskites under room temperature.
Researchers investigated exciton diffusion behavior in WSe2 monolayer flake under phonon scattering and disorder potentials. Temperature manipulation optimizes the competition between exciton localization and phonon-exciton scattering, leading to improved exciton diffusion coefficient.
Australian researchers have made a significant step towards ultra-low energy electronics by demonstrating the dissipationless flow of exciton polaritons at room temperature. The breakthrough involves placing a semiconductor material between two mirrors, allowing the excitons to propagate without losing energy.
A team of researchers from the University of Cambridge has identified a key loss pathway in organic solar cells that reduces their efficiency. By manipulating molecules inside the solar cell, they found a way to suppress this pathway and potentially overcome the hurdle for organic solar cells to compete with silicon-based cells.
Berkeley Lab researchers developed a method to increase the efficiency of LED devices by applying mechanical strain to thin semiconductor films. This approach reduces exciton annihilation, allowing for high-performance LEDs even at high brightness levels.
Exciton-polaritons exhibit non-linear effects, including Bose-Einstein condensation and polariton lasing without occupation inversion. The study reveals energy-degenerate parametric scattering of polaritons and opens up new avenues for research on multi-level polariton systems.
Researchers at ETH Zurich have produced a crystal consisting exclusively of electrons, overcoming previous obstacles due to the low mass and high motional energy of electrons. The team used light to excite excitons in the semiconductor layer, allowing them to visualize the periodic arrangement of electrons.
Scientists from the University of Tsukuba directly observed electron dynamics in organic film OLEDs, revealing a previously unknown feature of exciton decay. The study's findings may contribute to the development of more efficient OLED-based products.
Researchers from Rensselaer Polytechnic Institute demonstrate a new structure of correlated insulating state in TMDC materials, enabling greater control over excitons. This breakthrough is crucial for developing quantum emitters needed for future quantum simulation and computing.
Researchers at UNIST have successfully controlled the physical properties of naturally-formed nanoscale wrinkles in 2D semiconductors. The team developed a hyperspectral adaptive tip-enhanced photoluminescence spectroscopy approach to investigate and control the nano-optical and excitonic properties of wrinkles.
Researchers at the ARC Centre of Excellence in Exciton Science have discovered a 'sandwich' structure in 2D perovskite films used in solar cells. This layout encourages excitons to move from the central layer to both surfaces, helping to result in more efficient solar energy generation. Prototype devices have demonstrated 13% efficiency.
The City College of New York team demonstrated the use of Rydberg states to enhance nonlinear optical interactions in solid state systems, creating a chip-scale scalable single photon switch. This breakthrough enables the realization of quantum photonic technologies by amplifying scalability.
Researchers at OIST Graduate University have captured the first-ever image of an electron's orbit within an exciton using a revolutionary technique. The image shows the distribution of an electron around a hole inside an exciton, providing new insights into the nature of these fleeting particles.
Research on interlayer excitons in TMDs vdW heterostructures reveals ultrafast formation, long population recombination lifetimes, and intriguing spin-valley dynamics. The properties ensure good transport characteristics and pave the way for potential applications in efficient excitonic devices.
Researchers create ab initio NAMD method to investigate spin-valley exciton dynamics in MoS2, revealing e-h exchange interaction plays a crucial role. The new method provides a powerful tool for studying exciton relaxation, lifetime, dissociation, and defect interactions in solid materials.
Researchers at City University of Hong Kong have created a new type of LED using 2D perovskite materials, which can be processed at room temperature and offer improved efficiency. The team discovered that adding a simple organic molecule enhances the electro-luminescence performance of the material.
Researchers discovered an effect known as nonlinearity that can modify and detect extremely weak light signals using a quantum dot array. The team created an 'egg carton' of quantum dots in a 2D semiconductor, allowing for the control of energy levels with light.
The study of Cs2PbI2Cl2 reveals a threefold increase in photoconductivity at 2 GPa, comparable to 3D halide perovskites. Pressure regulation modifies excitonic features, reducing exciton binding energy and facilitating carrier dissociation.
Excitons can simultaneously show atomic-like and solid-like characteristics, with electrons and holes bound together in an atomic character or moving freely like waves in a solid. This discovery opens up new avenues for manipulating excitonic and materials' properties by light.
Researchers have found that halide perovskite nanocrystals exhibit extraordinary energy transport properties, allowing them to travel longer distances than conventional nanostructures. This discovery has significant implications for the development of high-efficiency solar cells and light-emitting devices.
Polaritons interact more than expected due to strong light-matter coupling and huge exciton-photon mass ratio. This challenges common assumptions about these quasiparticles, shedding new light on their interactions and applications in ultra-low energy electronics.
Researchers have directly visualized and measured elusive dark excitons in a new class of extremely thin semiconductors. This breakthrough technique could transform research and lead to significant advancements in fields like solar cells, LEDs, smartphones, and lasers.
Scientists have created a set of design guidelines to enhance the efficiency of molecular materials in solar cells. By understanding how particles travel through devices, researchers discovered that maximizing exciton diffusion length can improve organic solar cell performance.
Researchers at the ARC Centre of Excellence in Exciton Science have developed a new nanoscale building method that can arrange tiny gold rods into precise patterns. This technique has potential applications in renewable energy, smartphones, laptops, and efficient lighting, as well as improving security features in banknotes and passports.